Behr G, et al. - Authors ascertained the incidence of pneumorrhachis among patients with pneumomediastinum. They also determined if its proportion correlated with the extent of pneumomediastinum, and verified its clinical relevance. The presence of pneumorrhachis was noted in 5.8% of patients. In patients with the broadest distributions of mediastinal air, it was seen to be significantly more common and nonsignificantly more common in association with spontaneous as opposed to secondary pneumomediastinum. Findings suggested that in patients with pneumomediastinum, pneumorrhachis was a generally benign, self-resolving condition.